Windshield Wiper problem

I did a search but didn't see anything pertaining to my issue. A while back my wipers started acting funny on my 87 Tbird. Sometimes they would work and then sometimes they wouldn't, but I could usually get them to work after a couple of tries. Now they are not working at all. They will pump windshield fluid out but that is it. Any suggestions on how to diagnose and approach this problem? Thanks!

I'll send you some info circuits, parts locations and troubleshooting guide) if I can convince the scanner to cycle a few times.